Dark data is the info companies keep but never use—think old files, logs, or...

https://aged-wiki.win/index.php/Why_Is_Metadata_Tagging_a_Big_Deal_for_AI_Search%3F

Dark data is the info companies keep but never use—think old files, logs, or emails gathering dust. It makes up about 60-80% of stored data, yet often goes unnoticed. Ignoring it can waste around $2.5 million every year on storage and management